<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // var声明变量 = 赋值：将右侧的数据赋值给左侧的变量
        // var s = "hello world";  //string 字符串
        // console.log(s);
        // var _firstname1 = "xiaoming";
        // 驼峰命名
        // var firstName = "小明";
        // console.log(firstName)

        // 数据类型
        // var s = "hello world" //字符串 string
        // console.log(s);
        // var n = 100;  //数值 number
        // console.log(n);
        // var b = true  //布尔数据类型：真 false 假 

        //ctrl + /快捷键注释

        // var n1 = 20,n2 = 10;
        // //加减乘除 + - * /
        // var result = n1 / n2;
        // console.log(result);

        var s1 = "100" , s2 = "200";
        var result = s1 + s2;
        console.log(result);
    </script>
</body>
</html>